cpperror.c (cpp_error): For traditional CPP, default to diagnostics on pfile->line.

	* cpperror.c (cpp_error): For traditional CPP, default to
	diagnostics on pfile->line.
	* cpplib.c (prepare_directive_trad): Set line number for
	diagnostics for #define too.
	* cpptrad.c (skip_whitespace): Skip comments properly.
	(_cpp_expansions_different_trad): Initialize quote2.
testsuite:
	* gcc.dg/cpp/trad: New directory with traditional tests copied
	from parent directory.
	* gcc.dg/cpp/assert_trad1.c, gcc.dg/cpp/assert_trad2.c,
	gcc.dg/cpp/assert_trad3.c, gcc.dg/cpp/defined_trad.c,
	gcc.dg/cpp/hash2.c, gcc.dg/cpp/tr-define.c, gcc.dg/cpp/tr-direct.c,
	gcc.dg/cpp/tr-sign.c, gcc.dg/cpp/tr-str.c, gcc.dg/cpp/uchar-2.c:
	Move to trad/ and rename.
	* gcc.dg/cpp/trad/__STDC__.c, gcc.dg/cpp/trad/comment.c,
	gcc.dg/cpp/trad/escaped-eof.c, gcc.dg/cpp/trad/redef1.c,
	gcc.dg/cpp/trad/redef2.c: New tests.
	* gcc.dg/cpp/trad/trad.exp: New driver.

From-SVN: r54870